Mass Hallucinations

Mass Hallucinations is a fantastic virtual mirror. Within the decorative
frame, the viewers see their images in the display. However, unlike a true
mirror reflection, their faces are distorted in real-time based on their
distance from the frame and from other faces reflected in the mirror.

Fast automated detection and tracking of
faces is the technical key to this piece. Using a half-silvered mirror, two
cameras observe the viewers along the same optical path that the viewers
observe the display. These images are analyzed to track the viewers. Three
different techniques are combined to produce robust results: a stereo vision
module separates nearby people from the background, a color module detects
regions of skin hue, and a pattern module recognizes contrast patterns that
appear to be faces. The dynamic graphical effects are created by applying
distortions to the live video signal in the regions of the image containing
faces. These distortions follow the viewers' faces as they move in front
of the display, encouraging the viewer to attempt to manipulate their image
through their movements and expressions.

This demonstration shows how computers
can begin to observe and analyze visual information quickly enough for use
in interactive systems, allowing the user to control a display directly without
a mouse or keyboard.